The superstitious symbolism of a black cat crossing one's path is dependent upon culture: some cultures consider this a sign of impending bad luck, while some cultures consider this a sign of impending good luck.
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Placing keys on a table is considered unlucky. (Sweden)
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It's bad luck to leave a house through a different door than the one used to come into it.
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If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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If one walks underneath an open ladder it is said to bring bad luck. Sometimes it is said that this can be undone by immediately walking backwards back underneath the ladder.
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An acorn should be carried to bring luck and ensure a long life.
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In Asia, the digit 4 never appears in any Nokia handset model number, because 4 is considered unlucky in many parts of Southeast/East Asia.
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